Test indicator



Mafy 3K1, 1932. c. B. cLARKsoN TEST INDICATOR Filed March 13, 1929 www l. Illu...

INVENTQR QWQQJMAUORNEX i 50 mechanism, and'` Patented Mayy 31,l 1932 UNITED STATESPATENT oFFicE Y cLAnnnqB. oLnnxsoN,y or lismnenronfig..colvnnc'rrcn'r TEST INDIcAcion Aipplication led March 13, 19,29. Serial No. 346,548.V

My invention relates to test indicators of u the type used for accurately truing up or centralizing work for machining on the variously-types of machine tools, one of its principal features being to provide the instrument with a cylindrical dial withV the indiveating end of its pointer encircling the dial Vso that therpointerk and the readings on the dial -will always be visible to the operator during. the rotation of the indicator. Instruments of like character have been provided with graduated dials that are out of the operators vision for a greater part of the ro-` L 28.5 partly broken.

Figure 3 is a broken planview withth cover removed. n

Figure 4 is abroken plan View partly in section with the cover removed.

Figure l5 is an enlarged view in perspectiveof the ring pointer and broken view of its actuating rod. Y *Y v p Figure 6 is an enlarged view ofthe dial .Y mechanism online 6-6` of Figure '7.

Figure 7 is an enlargedbroken elevation partly in section of the dial and some of` its mechanism u l -f i Figure 8 is an enlarged bottom plan view Vof the' dial nut and'rod sections.

Figure 9 is a side Velevation ofthe cover.

Figure 10 is an enlarged broken view part- .ly'in section ofwajpart of the internal mechanismpof the device. v Y f f Figurell vis a detail view of the dial sup- Figure 12 is Ia modified viewwh-erein the rod itself forms the dial encircled by the ring pointer. f i Y f Figure 13 is a partv of the lever ,actuating ure 1, under friction. -contact between the rod 20 and the shortrod Figure 14 is'an enlarged plan view of the ring pointer. 'y y l represents the body of the instrument having integral therewith the fork 2 on one Y y end, and the hub 3 on the opposite end, and 55 4 is the cover secured to the body by the screws 5. n j

6 is an arm having Vthe outer forked end 7 yand the inner forked end 8 operativelyv lo cated within the fork 2 of the body as seen 60 more clearly in Figure 10. 9 is a ybolt projecting through one of the sides of the fork end 2, and also through one of thesides of the kforked end 8 of the arm 6. The innerV end of the bolt has the taper head l0 seated 55 in a correspondingly tapered recess of theA fork V8. On the outer threaded end of the boltis mounted the adjusting nut 11 adapted yto maintain the arm 6 in frictional contact' with the fork 2. The oppositeside of the 7-0 forked end 8 is mounted on the pintle l2 of the plug '13. The arm 6 is journaled on the bolt and pintle and it may have more or less sidemovement, see dotted lines 14, Fig-- section 25 must be located, Figure 20, as near as possible on the axis of the journals Von which the arm 6 has a lateral movement. If

'said contact'is above or below saidy axis it 80 will form ja leveragethat'will actuate the pointer when the arm 6 is moved out of axial alignment withV the dial. The movement transmitted by thecam 15 through the compound levers is too slight to perceptively S5 vchange the position of said ball and'socket connection with respect to said axis.

'Referring to Figures 1, 2`and 4, 15v is a cam located inthe forked end 7 of the arm 6 and journaled on the pin 16. The opposite 90 forkedrendyof this cam carries the ball contact Y 17 "frictio'nally held to the cam by the screw 18. Y19',-Fig. 4, is an opening through the Vaxis of the arm 6 for the small rod 20 on whose'outer threaded end 21 is mounted the 95 head 22 normally resting on the lowest point of the cam 15. The Vthreaded connection between the rod 20 andhead is for the purpose of taking up the wear of the several Contact .y points of the mechanism; 100

The ball and ysocket connected to the reciprocating slide 31 by.

means of the link 32. This slide is mounted on the rods 33 anchored in the inner end-ofV the nut 34, see also Figure 8.

35, Figures 4 and 11, is a stud Whose inner threaded'end 36 is seated in a. threaded hole in the outer end of the nut 34. Referring also to. Figure 6, 37 is the dial of paper or other suitable material closely wrapped about said stud. 38 is a hole extending kthrough the axis of this stud and the nut 34. 39 is a longitudinal kerf cut through onel side of the stud and the dial 37.

40, Figures 3, 4, and 7, is a small pointer rod whose inner end is journaled, not shown, to the lower end of the pin 41 of the link 32. This rod passes freely through the central opening of said stud andnut and itsy offset outer end a is attached to the ring pointer 42 encircling the dial 37 as also seen in Figure 6. The kerf 39 in the side ofthe stud 35 and dial 37 will provide a free passage for the oiset part40a of the pointer mechanism during the movement of the pointer over the dial.

To avoid frictional Contact of the ring pointer 42 with the dial, or its rod 40 with the sides of the axialopening in the stud 35 and nut 34, I prefer to lengthen the offset arm 40, Figure 14, sufficient to form the spiral shaped ligure 43 as an integral part of the rod 40. The part 43 will practically fill ythe central opening 38 of the stud and without frictional Vcontact therewith, and thus centralize the rod 40 and yalso permit a closer relation between the ring point-er anddial. It is quite evident that the paper dial could be dispensed withy and the body of the stud 35, Figure 12could be graduated and utilized as a cylindrical dial To protect the ring-pointer, I prefer to sur,- roundit and the cylindrical dial with the tube 44 of any transparent and unbreakable material, and to seat thesame in the recess 45,

lFigureV 4, of the collar 46 and the .recess ,47

ofthe nut 34. l

In use, the outer end of the stud 35 may be held in drill press chucks, adapters, or

other suitable holding means, or extension ytools can/,be inserted in the opening48 of the body. lVhen truing up work, the Contact ball 17 of the rotatable instrument is brought against the surface of the work,y andthe sightest unevennessl o r eccentricity'thereof will tilt the lever leandvsend its impulse through the various connected mechanism to the ring pointer 42. The compound lever feature will minimize the amount of movement necessary for the mechanism connected with the arm 6, so that, the slightest impulse given to the levers 28 and 30, will correspondingly increase the travel of the ring pointer over the face of the cylindrical dial, and all irregularities of any part of the work will always be visible to the operator regardless of the instruments position, and when the ring pointer remains stationary during' the truing up process, the operator will know that the Work is true.

While the delicate spring 49 will easily return the several moving parts to their lnormal positions, Figure 3, it will offer no .apprecla-ble resistance to a movementin the opposite direction yas rshown in Figure 4.

This spring simply keeps the levers 28 andy 30 in contact in any position they may occupy.

The frictional engagement of the contact ball feature with the cam 15, willpermit it to give Way and slightly tilt when meeting with an unevenness of the Work being tested.

But when the resistance is ytoo great for the ball to overcome, the arm 6 will laterally respond and thus prevent injury to the instrument. The portions of the cam 15 projecting outsidefof the arm 6 can also be used as contact points, and especially on flat surfaces.

While I show an intermediate compound leverage system for transmitting movement from the cam 15 to the ring pointer, any simple and equally effective means may be substituted therefor. f

The advantage derived from an instrument ot this character and construction will be greatly appreciated by all skilled workmen, as the cylindrical dial, and its encircling pointer, will always be visible to the operator in whatever position the instrument is placed Having thus described my invention what I claim is e l. A testA indicator of the character described having a graduated cylindrical dial, said dial having an axial openinga pointer encircling the dial having a depending rod in said opening, a body having a chamber,

Ia nut detachably mounted on the body, said -slide and to the free* end of the primary lever, the free end of the secondary lever being in operative contact with the primary lever. f f

y2. AV test indicator of the character described, comprising a body member having a chamber pointer mechanism, comprisingy a pointer rod and slide primary and secondary levers pivotally mounted in said chamber, the free end of the primary lever-pivotally connected to the slide, and the free end of the latter lever in pivotal contact with the primary' lever, `said body having an opening therethrough, a bushing fixed in said opening, a rod section mounted in said bushingl and Whose inner end projects into said Chamber and normallyk contacts with said secondary lever, said body having a forked extension, journals mounted thereon, an elongated arm having a forked extension pivotally supported on said journals, said arm havingan axial opening therethrough, a cam member pivotally supported to the outer end of said arm, a Work Contact member frictionally pivoted to the cam, a rod operatively mounted in the axial opening of the arm Whose outer end contacts With said cam, and Whose inner end has a ball and socket connection with the outer end of said rod section, said ball and socket connection being located on the axial line of said journals so that the movement of the arm Will not actuate ythe dial mechanism.

3. A construction as in claim 2in which said journals comprise a stud having a pintle mounted in one branch of the forked eX- tension of the body, a rod in the opposite branch of said forked extension, the forked end of the arm being journaled on said pintle and rod, the inner end of said rod having a retaining head bearing against the inner face of a branch of the forked arm, and a nut mounted on the rod to maintain the arm in frictional engagement With the forked eX- tension of the body. n

In testimony whereof I aix my signature.

CLAUDE B. GLARKSON. 

